Safety device for ski-securing means



June s, 1965 G. MAGNIN 3,188,104

SAFETY DEVICE FOR SKI-SECURING MEANS Filed Jan. 11, 1963 2 Sheets-Sheet 2 8 8 QEIEIIIQQ United States Patent "ice SAFETY DEVICE FOR SKI-SEUR1NG MEAN Georges Magnin, La Chaux-de-Fonds, Switzerland,

assignor to Secuma, La Chaux-de-Fonds, Switzerland Filed .Fan. 11, 1963, Ser. No. 250,831 Claims priority, application Switzerland, Apr. 4, 1962,

' 4,115/62 2 Claims. (Cl. 280-4155) Safety devices are known for ski-securing means which include a stationary member rigid with the ski and a movable member adapted to move over the stationary member so as to release the skiers shoe when the latter is subjected to a dangerous strain, the two members being locked together by elastic means which are released when said strain reaches a predetermined value.

Such devices show generally the drawback consisting in that they release the tip of the shoe which they are to hold fast on the ski only after an angular shifting of a comparatively considerable amplitude executed by the movable member which may frequently lead to a breaking of the'lowcr limbs of the skier. They are furthermore generally made of aluminium or of steel so that they require a constant upkeep, if it is desired for their operation to be performed normally when necessary and in particular their 7 upkeep requires a lubrication of the contacting surfaces between the movable and stationary members.

Now, my invention has for its object a safety arrangement of this type which removes the above drawbacks and is characterized by the fact that at least a fraction of the portion of one of said members in contact with the other member is made of plastic material so as to further the disengagement of saidmembers, by reason of the selflubricating properties of such a material.

The accompanying drawing illustrates, by way of example, two embodiments of myinvention.

In said drawings:

FIG. 1 is a plan view of an arrangement according to a first embodiment in its operative position,

FIG. Zrisa cross-section through line Il-'II of FIG. 1,

FIG. 3 is a detail cross-section through line IIIIII of said FIG. 1,

FIG. 4 is a plan view similar to FIG. 1 for another operative position of the device,

FIG. 5 is a cross-section through line VV of FIG. 4,

FIG. 6 is a plan view of the device according to the second embodiment,

FIG. 7 is a cross-section through line VII-VII of FIG. 6,

FIG. 8 is a plan view similar to FIG. 6, for another operative position of the device,

FIG. 9 is a cross-section through line IX-IX of FIG. 8.

The stop illustrated in the drawing (FIG. 1), provided for holding fast the front section of a shoe, which is not illustrated, on a ski 1, includes a support 2 adapted to be secured to the ski, for instance by means of screwsZa-and is provided with three recesses 5, of a semi-spherical shape.

for instance, arranged symmetrically with reference to the axis of the bore 4 and at equal distances from one another.

Inside the bore 4 is housed a bolt 6, the head of which .is of the same size and shape as the section 40 of said bore while its shank is of the same size and shape as the section 41). A coil spring 7 is held fast between said head 3,188,1d4 iatented. June 8, 1965 and the step between the sections 4a and 4b of the bore.

The jaw 3 is constituted by a block showing, on the one hand, a cylindrical recess 3a having a diameter slightly larger than that of the upright 20 which it caps while its bottom is provided with three projections 8 positioned and shaped in a manner corresponding to the recesses 5 in the rotary support 2, and on the other hand, an opening 312 along which the upper end of the bolt 6 extends. Said block or jaw 3 is held tight on the support 2 bya nut 9 which may be screwed home to a varying extent over the end of the bolt 6 according to the clamping stress desired. The nut is provided on its lower surface in contacting relationship with the block 3 with three projections 9a, preferably of a semi-spherical shape, which engage the corresponding recesses 811 provided in said block.

The part of the jaw adapted to engage the skiers shoe is relieved at 30 to match the shape of the end of the shoe sole and to enclose said shoe between a lateral flange 3d and an incurved surface 3e defining said relieved part. In the embodiment illustrated in the drawing, the arrange ment is provided with a shim or filling plate 10 secured to the lower surface of therib 3d when the sole of the skier is of a much smaller size than that provided for by the relieved part 3c, in particular in the case of ladies and childrens shoes. To this end, said plate, which matches exactly the outline of the rib 30', is provided with a dovetailed securing tongue 19a adapted to engage, as illustrated, a corresponding groove 3f, formed in the incurved surface 3!: of the support 3.

Under normal conditions of operation, the stop 2-3.is in the position illustrated in FIGS. 1 and 2 and the jaw 3 is held at apredetermined level by a stud 3g rigidly secured to it and engaging a slot 2d formed in the support 2 (FIG. 3

When the jaw is subjected to a stress which is comparatively reduced and is substantially perpendicular to the bolt 6, so that it extends for instance, in the direction of the arrow 1 of the drawing, said jaw is held in said position through cooperation between the spring 7 and the projections 8 on the jaw which projections engage the recesses 5 in the support 2.

If this stress becomes excessive, for instance upon falling of the skier, the projections 8 engage the edges of the corresponding recesses 5 and show a tendency to rise out of said recess, in antagonism with the spring 7, the jaw being then free to pivot on its support round the bolt 6, in the direction corresponding to the stress to which the jaw is subjected. During the movement thus imparted to the jaw, the stud 3g has of course moved out of the slot 2d in the support 2, the shape of which i slot is designed so as to allow a release of said stud, with- 'out opposing the upward movement of the jaw with reference to its support.

In fact, during the angular movement of said jaw, the projections 8 which have entirely disengaged the recesses, rest on the upper surface of the support in a manner such that said jaw lies at a higher level than that shown in the previous position illustrated in FIGS. 1 and 2. The end of the shoe which is normally clamped by said jaw is thus free to move in a vertical direction.

According as to whether the jaw rotates towards the left hand side or towards the right hand side of the drawing (FIGS. 1 and 4) the nut 9 moving with the jaw 3 is screwed or unscrewed with reference to the bolt 6, the nut being held on the jaw by its projections 9a. It is thus unnecessary for the skier to proceed after each fall 7 with a further adjustment of the clamping pressure exerted by the jaw on the support 2 through adjustment of said unit, since the latter returns automatically into the position obtained after its first adjustment, whenever the jaw is returned into a position symmetrical with reference to the axis of the ski.

In order to retain the same safety conditions whatever may be the condition of the snow, the clamping stress must of course remain constant, undervery different atmospheric conditions. Thus, the support and the jaw are made of plastic material of which the frictional coefficient is comparatively low, is, as well known, practically not sensitive to moisture and to modifications in temperature. Said stop is in fact self-lubricating and does not require any particular upkeep.

According to a first modification, the support may be made of metal, for instance aluminium, the jaw being made of plastic material, the results obtained being then less satisfactory than those obtained with the precedingly referred to material.

According to a second modification, the jaw may be made of metal and the support of plastic material.

The plastic material used may be of any type of which the resistance to breaking increases, when the temperature drops. Thus, at about 20 C., said resistance reaches 900 kg. per sq. cm. and underneath 0., its value rises above 1000 kg. per sq. cm. in the case of materials such as those having a polyamide or polyurethane base, chiefly a derivative of polyamino-capronic acid associated with molybdenum 'bisulfide or again a derivative of polyhexamethylene diadipate.

The second embodiment (FIGS. 6 to 9) is dilferent from that already described solely through the fact that the jaw '3 is provided with an incurved slot 30, through which the upper portion of the threaded rod 6 or bolt extends. The operation of said arrangement is slightly different from that described: in fact, the pivotal movement of the jaw, which is performed in the same manner as precedingly, is associated with a transverse sliding of said jaw over its support, which sliding as illustrated in the drawing (FIG. 8) is arrested by the impact of the left-hand edge of the slot 30 against the rod 6.

The projections and the recesses provided in the parts 2 and 3 may of course show various shapes diflering from those illustrated, chiefly elliptic, egg-shaped, conical, =frusto-conical, pyramidal or frusto-pyramid-al shapes.

Furthermore, the projections 8 may be provided on the support and the corresponding recesses on the jaw. Similarly, the projections locking the nut 9 may be arranged on the upper surface of the jaw, the corresponding recesses being provided then in the lower surface of said nut.

What I claim is:

l. A safety system for ski securing means comprising a first member rigid with the ski, a second member engaging the skiers shoe and adapted to move over the first member between an operative position clamping said shoe in position and a position releasing the shoe under the action of external stresses above a predetermined value, one of said members being provided with an elongated horizontal transverse slot, a vertical cylindrical pivot rigid with the other member, engaging said slot and adapted to horizontally and vertically slide therein, the diameter of said pivot being substantially equal to that of the slot, at least one of said members being made of a self-lubricating plastic material in at least part of its surface engaging the other member, one of said members being provided with at least one recess in its surface engaging the other member, a projection raised on said other member and normally engaging the corresponding recess in said one surface and elastic means fitted between said members urging them towards each other to hold said projection on said other surface inside the corresponding recess to lock elastically the two members against a relative vertical, angular and transverse shoe-releasing shifting .as long as the external stresses do not rise above said predetermined value.

2. A safety system for ski-securing means comprising a first member rigid with the ski, a second member engaging the skiers shoe and adapted to move over the first member between an operative position clamping said shoe in position and a position releasing the shoe under the action of external stresses above a predetermined value, a vertical cylindrical pivot carried by the first member and slidingly extending through and above the second member, a nut t hreadedly fitted over the upper end of said pivot to limit the vertical sliding movement of the second member over the pivot with reference to the first member, one of said parts, the nut and the second member, being provided with at least one recess and projections raised on the other part and engaging the corresponding recesses in the first mentioned part, at least one of said members being made of a self-lubricating plastic material in at least part of its surface engaging the other member, one of said members being prowided with at least one recess in its surface engaging the other member, a projection raised on said other member and normally engaging the corresponding recess in said one surface, and elastic means 'fitted between said members urging them towards each other to hold said said projection on said other surface inside the corresponding recess to lock elastically the two members against a relative vertical and angular shoe-releasing shifting as long as the external stresses do not rise above said predetermined value.

References Cited by the Examiner UNITED STATES PATENTS 2,383,064 8/45 Lanz' 280-1135 2,586,369 2/52 Hvam 28011.35 2,846,232 8/58 Schnell 28011.35 3,000,644 9/61 Beyl 280-11.35 3,079,464 2/ 63 De Place 280 1 1.35

FOREIGN PATENTS 196,292 3/ 58 Austria.

A. HARRY LEVY, Primary Examiner. 

1. A SAFETY SYSTEM FOR SKI SECURING MEANS COMPRISING A FIRST MEMBER RIGID WITH THE SKI, A SECOND MEMBER ENGAGING THE SKIER''S SHOE AND ADAPTED TO MOVE OVER THE FIRST MEMBER BETWEEN AN OPERATIVE POSITION CLAMPING SAID SHOE IN POSITION AND A POSITION RELEASING THE SHOE UNDER THE ACTION OF EXTERNAL STRESSES ABOVE A PREDETERMINED VALVE, ONE OF SAID MEMBERS BEING PROVIDED WITH AN ELONGATED HORIZONTAL TRANSVERSE SLOT, A VERTICAL CYLINDRICAL PIVOT RIGID WITH THE OTHER MEMBER, ENGAGING SAID SLOT AND ADAPTED TO HORIZONTALLY AND VERTICALLY SLIDE THEREIN, THE DIAMETER OF SAID PIVOT BEING SUBSTANTIALLY EQUAL TO THAT OF THE SLOT, AT LEAST ONE OF SAID MEMBERS BEING MADE OF A SELF-LUBRICATING PLASTIC MATERIAL IN AT LEAST PART OF ITS SURFACE ENGAGINT THE OTHER MEMBER, ONE OF SAID MEMBERS BEING PROVIDED WITH AT LEAST ONE RECESS IN ITS SURFACE ENGAGINT THE OTHER MEMBER, A PROJECTION RAISED ON SAID OTHER MEMBER AND NORMALLY ENGAGING THE CORRESPONDING RECESS IN SAID ONE SURFACE AND ELASTIC MEANS FITTED BETWEEN SAID MEMBERS URGING THEM TOWARDS EACH OTHER TO HOLD SAID PROJECTION ON THE OTHER SURFACE INSIDE THE CORRESPONDING RECESS TO LOCK ELASTICALLY THE TWO MEMBERS AGANIST A RELATIVE VERTICAL, ANGULAR AND TRANSVERSE SHOE-RELEASING SHIFTING AS LONG AT THE EXTERNAL STRESSES DO NOT RISE ABOVE SAID PREDETERMINED VALUE. 